Circuit breaker



July 28, 1953 T. M` COLE CIRCUIT BREAKER Filed Nov. 15, 1949 IN VEN TOR.

IAII

l w www n w F Patented July 28, 195,3

CIRCUIT BREAKER Thomas M. Cole, New York, N. Y., assignor to FederalElectric Products Company, Newark,

N. J., a corporation Application November 15, 1949, Serial No. 127,433

54 Claims. 1

This invention relates to automatic circuit breakers and moreparticularly, but without restriction, to circuit breakers of thegeneral type disclosed in United States Patents Nos. 2,174,669 datedOctober 3, 1939, 2,209,319, 2,209,352 and 2,209,353 each dated July 3D,1940 `and Re. 23,188 dated January 10, 1950.

One object of the present invention is the provision of a circuitbreaker of the type referred to with improved means for operativelyconnecting the handle to the movable contact member.

Another object is to provide a construction which enables theelimination of insulation between the movable contact member and thelever which is connected thereto for moving said contact member.

Another object is the provision of a circuit breaker having an arcingchamber of improved construction.

A further object is the provision of an improved terminal arrangementand construction.

The above and other objects, features and advantages of the inventionwill be fully understood from the following description, considered inconnection with the accompanying illustrative drawings.

In the drawings:

Fig. 1 is a side view of a circuit breaker embodying the presentinvention;

Figs. 2 and 3 are end views as seen from lines 2-2 and 2 3,respectively, of Fig. 1;

Fig. 4 is a side view of the circuit breaker, one part of the casingbeing removed, the circuit breaker mechanism being open;

Fig. 5 is a view similar to Fig. 4 showing the circuit breaker mechanismclosed;

Fig. 6 is a sectional View on the line 6-6 of Fig. 5;

Fig. '7 is a sectional view on the line l-l of Fig. 5;

Fig. 8 is a fragmentary sectional view on the line 8 8 of Fig. 5; and

Fig. 9 is a perspective view of the actuating member of the circuitbreaker, a portion thereof being cut away for the purpose ofillustration.

Referring now to the drawings in detail, the circuit breaker of thepresent invention comprises a two part insulation housing or casing I0formed by body part i2 and the cover or closure part i4, each of saidparts being formed of insulation material preferably by a moldingoperation, and being secured in housing-defining relation in anysuitable way, for example by bolts I6.

In the illustrated embodiment of the invention, the circuit breaker isof the plug-in type for use with a terminal plate assembly such as thatdescribed in application, Ser. No. 127,432 led November 15, 1949, by meand Paul M. Christensen. as joint inventors, and assigned to theassignee of my present application. It will be understood, however, thatthe present invention is not limited to plug-in circuit breakers but isapplicable as well to circuit breakers which are not provided withplug-in terminals. The housing is provided, above a re-entrant portion20, with a chamber 22. A plug-in terminal prong or stab contact 24 ismounted vertically in said chamber, said stab contact being adapted formaking contact with said terminal block unit and being provided with thelaterally extending portions or arms 28 which are removably positionedin cooperating recesses 2l formed in the walls of said chamber, asillustrated and described in said application. It will be understoodthat any other suitable type of stab contact may be used in place of thestab Contact 214 illustrated in the drawings herein, for example, andnot by way of limitation, the other form of stab contact illustrated anddescribed in the above identied copending application.

The casing is provided, above the open recess i8 therein, with an arcingchamber 28 in which the stationary contact 30 and the movable contact 32are disposed for relative movement. It will be noted that said arcingchamber is bounded by the similarly thickened portions 34, 35 and 38 ofwall 40 of the body part, and by the portion 42 of said wall, whichextends between the portions 38 and 38, and which is thickened to alesser extent than said other portions. It Will be noted also thatportion 38 is provided with a shoulder 44 where it extends above portion42 and that portion 35 is provided with an angular step 4t where itextends above portion `ft2. The cover part i4 is provided on its innersurface with a thickened portion 48 having a form complementary toportion 42 of wall 40. When the body and cover parts are inhousing-defining relation, the ends 50 and 52 of said portion i8 abutthe shoulder 44 and the step 46, respectively, as illustrated in Fig. 8,and said portion together with portion 42, the confronting surfaces ofwhich are spaced as at 55, form a bounding wall for the arcing chamberin opposition to the wall thereof formed by the thickened portion 34.Therefore, it will be noted that with the body and cover parts securedtogether, the casing is provided with an arcing chamber which is closedon all sides thereof except at its opening externally of the casingwhereby arcs which may be formed upon the disengagement of contacts 30and 32 3 are to a very considerable extent prevented from entering thatportion of the casing in which the circuit breaker mechanism iscontained.

A chamber 54 for containing the circuit breaker mechanism is formed bythe opposing raised edge portions 56 and 58 of wall 40, by the raisedportion 60 of said wall, which also bounds chamber 22, by portions 38,42 and 48 opposing said portion 60, and by wall 40 and cover |4. Theedge portion 56 is provided with an opening 62 therein through which ahandle 64 projects for manual operation of the circuit breakermechanism. The handle is formed of insulation material and is providedwith the laterally extending circular pivot portions 65, 65, which arepositioned in the bearing recesses 61, 61, respectively, formed in eachof the casing parts.

Referring now to the circuit breaker mechanism disposed in chamber 54,said mechanism includes a manually operable member, here shown as theabove-mentioned pivoted handle 64. A uni-planar movable contact member66, formed in one piece, is provided with a portion 58 having a highresistance to the ilow of current therethrough, and a portion 'I0 havinga low resistance to current now therethrough. Specifically, portion 66is formed of a high resistance metal, such as, for example and withoutlimitation, Nichrome or other suitable metal, and portion 'I0 is formedof a low resistance metal, such as, for example, and without limitation,bronze, or other suitable metal, and said two portions are secured toeach other in edge to edge relation in any suitable way, for example bywelding or brazing. Contact member 66 may be formed of powdered metal bya molding operation, with parts 58 and 'l0 of metal powder of high andlow resistance, respectively. Said movable contact member is mounted inthe chamber 54 for pivotal movement by pivot pin '|2, the opposite endsof which are received in the aligned bearing projections 'i4 on theinner surfaces of each of the casing parts. The low resistance portionis provided with the contact 32 which is engageable with anddisengageable from the companion stationary contact carried by theterminal member '|6, which will hereinafter be more particularlydescribed. It will be understood that in respect to other features ofthe invention, the latter are not limited to a movable contact member 65formed of different metals but apply as well to a circuit breaker inwhich the movable Contact member is formed of one metal, as in the abovementioned patents, for example. The aforementioned complementary casingportions 42 and 48 form a guideway for the movable contact member, thespace between the confronting surfaces thereof defining a guide slotthrough which an end portion 18 of the movable contact member projectswith slight clearance, as illustrated in Figs. ".1 and 8. It will benoted from Fig. 4 that the end portion 18 of the movable contact memberabuts step 45 in the disengaged condition of the companion contacts,said step serving to limit the movement of the movable contact member inits circuitopen position.

At its end portion 18, the movable contact member is provided with anintegral depending portion 80 which extends through a slot 82 at one endof a thermal-current responsive member 84 which, as here shown, consistsof a thermostatic bi-metallic flexible strip which is welded orotherwise secured at said end thereof to a side edge of movable contactmember 56. The free end of bi-metallic strip 84 is arranged toreleasably engage the latch element 86 at one end of an actuating memberor lever 88 pivotally mounted on the end of movable contact member 66opposite the end which carries the contact 32.

As here shown, the lever 86 is formed in one piece of sheet metal andcomprises the laterally spaced opposing walls 90, 90 open between themarginal edges 82, 92 thereof, and partially closed between the oppositemarginal edges 94, 04 thereof, by the integral wall 96 which is providedwith the aforementioned latch element 86, depending below said opposingwalls, and with the longitudinal reinforcing bead 98 offset laterallyoutwardly thereof. The walls 90, 90 are provided with the confrontingpunched-in, cylindrical projections |00, |00, respectively, which aremounted for pivotal movement in a bearing aperture |02 provided in themovable contact member 66 at the aforementioned opposite end thereof. Aninsulation bushing |03 is provided in bearing aperture |02 to insulatelever 88 from contact member 56, although this is not strictly necessarywhen said contact member has the high resistance portion 68 or whenlever 88 is made of a metal having a substantially higher resistancethan that of the movable contact member. It will be noted from Figs. 6and 7, that when the lever 88 is mounted on the movable contact member66, the walls 90 straddle said movable member. At their free ends, eachwall 90 is provided with an aperture |04. Gne end |06 of a resilientlink |68 extends with slight clearance through the aligned apertures |04(Fig. 6) and the other end of said link is pivotally engaged with theadjacent end of handle 64. A coil compression spring H0 is operativelyinterposed between the movable contact member 66 and handle 64 forbiasing the movable contact member to its open position. One end of saidspring engages a lug H2 carried by handle 64 and the other end of saidspring engages a lug |4 integral with the movable contact member 65. Themechanism constituted by handle 84, movable contact member 66, thermalstrip 84, lever 88 and link |08 is similar to and operates substantiallyin the same way as corresponding mechanism in the above identied UnitedStates Patent No. 2,459,427.

It will be observed that the U-shaped construction of lever 38 obviatesthe need for providing the movable contact member with the laterallyoffset parts provided in the movable contact member of said Patent No.2,459,427, and simplies the pivotal connection of said lever to saidmovable contact member and the insulation between said two members wheninsulation is required. Also, the surface of element 86 which engagesthe free end of strip 84 is free of burrs and is smooth so as not toimpede the release of strip 84 when the latter is deflected uponoverload.

Also as here shown, the movable contact member 66 is provided with agenerally circular, peripherally interrupted, tapered aperture ||6 and atapered pin ||8 for Calibrating the circuit breaker. Said aperture isformed in the marginal edge of said movable contact member at thejuncture of the narrowed portion |20 thereof, on which lever 88 ispivotally mounted, and the wider body portion |22 thereof. It will beunderstood that as pin |8 is forced into aperture ||6, the portion ofthe movable contact member at the right of pin ||8 (Figs. 4 and 5) isbent upwardly in its own plane to decrease the amount of overlap of thedetent element 86 at the edge |24 of strip 84 so that less deflection ofsaid strip is required to trip the breaker.

It will be understood that member 84 operates to latch the manuallyoperable actuating mechanism 68 to the movable contact member 66 and tounlatch the actuating mechanism from the movable contact member, theunlatching taking place upon deflection or" member 84 causing thedisengagement of end |24 thereof from the edge of latch element 86 oflever 88 upon the occurrence of an overload or under other abnormalpredetermined current conditions in the circuit controlled by thecircuit breaker. When member 84 is deflected from engagement with lever88, spring H8 is eirective to move contact member 66 to its openposition, i. e., from the position illustrated in Fig. 5 to the positionillustrated in Fig. 4. As heretofore mentioned, the step 46 constitutesa stop for the member 66 to limit the opening movement of the latter.

The thermal element 84 is connected in series with movable Contactmember 66 and the circuit which is to be controlled by the circuitbreaker. For this purpose a flexible metallic conductor or connector |26is connected to said thermal element, preferably adjacent to the freeend |24 thereof, and extends from chamber 54, through an opening 6| inwall portion 60, into chamber 22 for connection to the stab contact 24which makes contact with a power line in the terminal panel assembly ofthe co-pending application described above. although member 84 is inelectrical contact with the movable contact member 86 through lever 68,in the closed condition of the circuit breaker, it will be understoodthat due to the high resistance characteristic of the material formingportion 68 of the movable contact member, the current will not by-passmember 84 by flowing through the lever but substantially all the.current will iiow through member 84 into portion 'i6 of the movablecontact member and through the engaged contacts 36 and 32. To achievethe same result, it will be understood that the movable contact memberneed not be formed of portions having high and low resistancecharacteristics, but that the actuating member 8e may be formed of ahigh resistance material, such as Nichrome, or other suitable material,to prevent the flow of current therethrough and into the movable contactmember.

Load terminal 16, which carries the stationary contact 38, is positionedin an open recessed portion |28 formed in the casing. Said terminalcomprises an integral conducting strip |30 which is shaped to form thevertically disposed opposing walls 32 and |34, and the horizontallydisposed oppcsing walls |36 and |38 of the terminal, when the casing ismounted in the position illustrated in Figs. l through 5. Une endportion |48 of said strip extends inwardly beyond wall |34 and carriesthe stationary contact 30. The inner end of part |48 abuts the shoulderportion |42 defined by wall portion 38 of the casing body to positioncontact 88 in relation to contact 32. The lower end of wall |34 is ofreduced width and passes through an opening in wall |38 and is bentunder the latter as indicated at |48. Said end portion |46 is providedwith the laterally extending projections |44 which extend into alignedrecesses |46 in the confronting surfaces of Iboth casing parts. Portion|48 abuts a stop |58 formed in portion 34 of body part |2 and overlyingan extending portion |52 thereof. It will ybe noted that when the covermember 4 is 6 secured to the body part I2, thev terminal .16 cannot beremoved from the casing, movement in a horizontal plane being preventedby shoulder |42 and stop |58, and movement in a vertical plane beingprevented by the arms |44 positioned in the recesses |46, and theunderlying projection |52 and the overlying portion |54 of wall portion38 which abuts the upper surface of stripy portion |46. A terminal screw|56 is engaged in a threaded aperture in wall |36 and aperture |58 isformed in wall |32 for the insertion of a lead wire between saidterminal screw and the,

upper surface of wall |33.

As illustrated, the thermal current-responsive member 84 is preferablyoperable not only in response to the heating eiect of the currentpassing therethrough, but is also operable under the control ofelectro-magnetic means for effecting disengagement of the companionrelatively movable contacts 38 and 32, and the arrangement is preferablysuch that, as here shown, the electromagnetic means is energized by thecurrent which passes through the said thermal current-responsive member.For this purpose an electro-magnetic member |66 is fixedly secured,preferably by welding, or in other suitable manner, on member 85| nearthe free end thereof and a companicn rigid armature |62 is disposed inspaced confronting relation to electro-magnetic member |68. As shown inFig. 6, magnetic member |68 straddles member 84 by which it is carried.Said member |68 is formed in one piece of soft sheet steel or othersuitable sheet metal and is provided with an end wall, opposed sideWalls, and with cut-turned end portions |64 which are arranged insurface-confronting relation to the adjacent surface of armature |62. Asshown in Fig. 8, armature |62 is provided with a slotted portion |66,opposite the free end thereof, which is aligned with slot 82 in member84. The armature is secured to the xed end of member 84, preferably bywelding, and side portions |68 thereof are .bent around the marginalside edges of member 84, the depending portion of movable member 66extending through said aligned slots and being riveted to the outersurface of the armature. At its free end, the armature is provided withthe out-turned portions |10 which are disposed in spaced confrontingrelation with the portions |64 of the electro-magnetic member |68. Theelectro-magnetic member |60 and the armature |62 operate substantiallyin the same way as corresponding mechanism in said United States PatentNo. 2,459,427.

The subject matter or" the present application, which is concerned withcalibration of the circuit breaker, is related to my copendingapplication Serial No. 213,591, filed March 2, 1951, and assigned to theassignee hereof.

`While l have shown and described the preferred embodiment of myinvention, it will be understood that the latter may be embodiedotherwise than as herein speciically illustrated or described and thatin the illustrated embodiment certain changes in the details ofconstruction and in the arrangement of parts may be made withoutdeparting from the underlying idea or principles of the invention withinthe scope of the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. In an automatic circuit breaker having a stationary contact, amovable contact engageable and disengageable therewith, actuating meansfor operatively effecting the engagement thereof and athermally-responsive lai-metallic strip for eiecting the disengagementthereof; a uni-planar movable contact member on which said movablecontact and said strip are bodily carried, said actuating means beingpivotally carried thereby and being in normal engagement with said stripto prevent relative pivotal movement.

2. In an automatic circuit breaker having a stationary contact, amovable contact engageable and disengageable therewith, actuating meansfor operatively effecting the engagement thereof and athermally-responsive bi-metallic strip for effecting the disengagementthereof; the combination with said actuating means of a uniplanarmovable contact member on which said movable contact and said strip arebodily carried, said actuating means comprising a member straddling saidmovable contact member, and pivotally carried thereby, said straddlingmember being in normal engagement with said strip to prevent relativepivotal movement.

3. In an automatic circuit breaker having a stationary contact, amovable contact engageable and disengageable therewith, actuating meansfor operatively eiecting the engagement thereof and athermally-responsive bi-metallic strip for eiecting the disengagementthereof; the combination with saidactuating means of a movable Contactmember on which said movable Contact and said strip are bodily carried,said actauting means being pivotally carried thereby and being in normalengagement with said strip to prevent relative pivotal movement, saidactuating means comprising a lever member in direct electrical contactwith both said strip and said movable contact member, one of saidmembers being of such character as to cause substantially all of thecurrent in the circuit to pass through said strip.

4. in an automatic circuit breaker having a stationary contact, amovable contact engageable and disengageable therewith, actuating meansfor operatively effecting the engagement thereof, and athermally-responsive bi-metallic strip for effecting the disengagementthereof; the combination with said actuating means of a movable contactmember on which said movable contact and said strip are bodily carried,said actuating means being pivotally carried thereby and being in ,o

normal engagement with said strip to preventv relative pivotal movementbetween said movable contact member and said actuating means, saidactuating means comprising a lever member in direct contact with bothsaid strip and said movable contact member, and means integral with oneof said members for directing substantially all of the current in thecircuit through said strip, said last mentioned means comprising aportion of said movable contact member having a low resistance tocurrent flow and a portion thereof having a high resistance to currentow, said low resistance portion being in the path of current flowbetween said strip and said movable contact and said high resistanceportion being in the path of current flow between said lever member andsaid movable contact.

r In an automatic circuit breaker having a stationary contact, a movablecontact engageable and disengageable therewith, actuating means foroperatively effecting the engagement thereof and a, thermally-responsivelai-metallic strip for keifecting the disengagement thereof; thecombination with said actuating means of a movable contact member on.which said. movable contact and 8 said strip are bodily carried, saidactuating means being pivotally carried thereby and being in normalengagement with said strip to prevent relative pivotal movement, saidactuating means comprising a member straddling said movable contactmember and in direct contact with both said strip and said movablecontact member, said straddling member being formed of a material havinga high resistance to current ow whereby substantially none of thecurrent in the circuit will oW therethrough.

6. In an automatic circuit breaker having a stationary contact, amovable contact engageable and disengageable therewith, actuating meansfor operatively effecting the engagement thereof and athermally-responsive bi-metallic strip for eiecting the disengagementthereof; the combination with said actuating means of a movable contactmember on which said movable contact and said strip are bodily carried,said actuating means being pivotally carried thereby and being in normalengagement with said strip to prevent relative pivotal movement, saidactuating means comprising a lever member in direct contact with bothsaid strip and said movable Contact member, said lever member beingformed of a material having a high resistance to current now wherebysubstantially none of the current in the circuit will now therethrough.

7. In an automatic circuit breaker, a stationary contact, a movablecontact member provided with a contact engageable with and disengageablefrom said stationary contact, manually operable actuating means, and acurrent-responsive member for eiecting disengagement of said contacts inresponse to predetermined current in the circuit, saidcurrent-responsive member being movable relatively to said movablecontact member for latching the latter to and unlatching it from saidactuating means, said actuating means being a lever provided withportions straddling said movable contact member and with portions inpivotal engagement therewith and having a part releasably engageablewith said current-responsive member.

8. In an automatic circuit breaker, a stationary contact, a movablecontact member provided with a contact engageable with and disengageablefrom said stationary contact, manually operable actuating means, and acurrent-responsive member for eiecting disengagement of said contacts inresponse to predetermined current in the circuit, saidcurrent-responsive member being movable relatively to said movablecontact member for latching the latter to and unlatching it from saidactuating means, said actuating means being a lever provided withportions straddling said movable contact member and with portions inpivotal engagement therewith, said lever having a latch element integralwith said straddling portions in position therebetween and in latchingengagement with said current-responsive member.

9. In an automatic circuit breaker having a stationary contact, amovable contact member provided with a contact engageable with anddisengageable from said stationary contact, manually operable actuatingmeans and a thermally-responsive bi-metallic strip for eieotingdisengagement of said contacts in response to predetermined current inthe circuit, said strip beingv carried by and bodily movable with saidmovable contact member and also movable relatively thereto for latchingthe latter to and unlatching it from, said actuating means; a dependingpor- Said strip,

tion carried by said movable contact member and extending through saidstrip, an armature having a surface portion in abutment with a surfaceof said strip and provided with confronting portions in engagement withthe opposite surface of said depending portion extending through saidarmature and being secured to an opposite surface portion thereof, and acompanion magnetic member carried by said strip and movable in relationto said armature in response to predetermined current in the circuitwhereby to move said strip to unlatch said movable Contact member fromsaid actuating means independently of the response of said strip it selfto the current.

l0. In an automatic circuit breaker having a stationary Contact, amovable contact member provided with a contact engageable with anddisengageable from said stationary contact, manually operable actuatingmeans, and a thermallyresponsive bi-metallic strip for effectingdisengagement oi said contacts in response to predetermined current inthe circuit, said strip being carried by and bodily movable with saidmovable contact member and also movable relatively thereto for latchingthe latter to and unlatching it from said actuating means; a dependingportion carried by said movable contact member and extending throughsaid strip, an armature having a surface portion in abutment with asurface of said strip and provided with confronting portions inengagement with the opposite surface of said strip, said dependingportion extending through said armature and being secured to an oppositesurface portion thereof, and a companion magnetic member carried by saidstrip and movable in relation to said armature in response topredetermined current in the circuit whereby to move said strip tounlatch said movable contact member from said actuating meansindependently of the response of said strip itself to the current, saidmagnetic member being secured to said strip against movement relativethereto.

l1. In an automatic circuit breaker having a stationary contacty amovable contact member provided with a contact engageable with anddisengageable from said stationary contact, manually operable actuatingmeans and a thermallyresponsive lei-metallic element for effectingdisengagement of said contacts in response to predetermined current inthe circuit, said element being carried by and bodily movable with saidmovable contact member and also movable relatively thereto for latchingsaid element to and unlatching it from said actuating means; means forcalibrating the movement ofk said element relative to said movablecontact member comprising a marginal edge portion of said movablecontact member in which is delined a peripherally interrupted aperture,and a tapered. member engaged in said aperture for displacing saidmarginal edge portion of said movable contact member so as to change therelationship of said bi-metallic element with respect to the main bodyof said movable contact member.

12. In an automatic circuit breaker having a stationary contact, amovable contact member provided with a contact engageable with anddisengageable from said stationary contact, manually operable actuatingmeans and a thermallyresponsive bi-metallic element for effectingdisengagement of said contacts in response to predetermined current inthe circuit, said element being carried by and bodily movablewith saidmovable contact r-mfelilber also movable relatively thereto for latchingsaid element to and unlatching it from said actuating means; means forcalibrating the movement of said element relative to said movablecontact member comprising a marginal edge portion of said movablecontact member in which is defined a peripherally interrupted aperture,and a tapered member engaged in said aperture for displacing saidmarginal edge portion of said movable contact member so as to change therelationship of said b-metallic element with respect to the main body ofsaid movable contact member, said marginal edge portion being at the-juncture of a narrower portion of said movable contact member and themain body thereof, said actuating means being mounted on said narrowerportion and said narrower portion being displaceable relative to saidmain body so as to change the relationship of said bi-metallic elementwith respect to said actuating means.

13. In an automatic circuit breaker, a casing provided with an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers being separated by a wall formed bycomplementary portions provided on confronting surfaces of said casing,one of said portions having raised end parts and the other of saidportions being removably engageable between said end partsy in abutmenttherewith, the

confronting surfaces of said portions deiining a guideway, a stationarycontact disposed in said arcing chamber, and a movable contact membermounted in the other chamber and having a portion disposed said guidewayand extending into said arcing chamber, said latter portion beingprovided with a movable contact engageable with and disengageable fromsaid stationary contact, said wall encompassing said latter portion forconfining arcing within said arcing chamber.

14. In an automatic circuit breaker, a casing provided with an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers being separated by a wall formed bycomplementary portions provided on confronting surfaces of said casing,one of said portions having raised end parts and the other of saidportions being removably engageable between said end parts, in abutmenttherewith, the confronting surfaces of said portions defining aguideway, a stationary contact disposed in said arcing chamber, and amovable contact member mounted in the other chamber and having a portiondisposed in said guideway and extending into said arcing chamber, saidlatter portion being provided with a movable contact engageable with anddisengageable from said stationary contact, said wall encompassing saidlatter portion for conning arcing within said arcing chamber, said endparts being shoulders formed in opposing walls of said arcing chamber,the ends of said other casing portion being retained againstdisplacement by said shoulders.

15. In an automatic circuit breaker, a casing having an open recessedportion and an arcing chamber adjacent thereto, said recessed portionand said arcing chamber being separated by an apertured portion of saidcasing forming a wall of said chamber, and a terminal member disposed insaid recessed portion and mounted on said wall, said member having acontact carrying part extending through said aperture and abutting thesurface of said wall opposite the surface on which said member ismounted.

l5. In an automatic circuit breaker, a casing having an open recessedportion and an arcing chamber adjacent thereto, said recessed portionand said arcing chamber being separated by an apertured portion of saidcasing forming a wall of said chamber, and a terminal member disposed insaid recessed portion and mounted on said wall, said member having acontact carrying part extending through said aperture and abutting thesurface of said wall opposite the surface on which said member ismounted, said wall having a step formed in said last mentioned surfacethereof and a shoulder at said rst mentioned surface thereof, saidcontact carrying part abutting said shoulder said terminal member havinga part engage said step.

17. In an automatic circuit breaker, a casing having an open recessedportion and an arcing chamber adjacent thereto, said recessed portionand said arcing chamber being separated by an apertured portion of saidcasing forming a wall of said chamber, and a terminal member disposed insaid recessed portion and mounted on said wall, said member having acontact carrying part extending through said aperture and abutting thesurface of said wall opposite the surface on which said member ismounted, said Wall having a step formed in said last mentioned surfacethereof and a shoulder at said first mentioned surface thereof, saidcontact carrying part abutting said shoulder and said terminal memberhaving a part engaged in said step, said terminal member comprising acontinuous strip, said latter part being at one end thereof and saidcontact carrying part being at the other end thereof.

18. In an automatic circuit breaker, an nsulation casing formed ofcompanion complementary parts mutually secured in housing-definingrelation, and a sta-b terminal member contained in said casing andhaving a portion extending therefrom for effecting contact between saidcircuit breaker and a companion contact terminal, said casing parts andsaid stab terminal member being provided with inter-engaging portionsfor releasably retaining said stab terminal member in operativedisposition in said casing.

19. In an automatic circuit breaker, an insulation casing formed ofcompanion complementary parts mutually secured in housing-definingrelation, and a stab terminal member contained in said casing and havinga portion extending therefrom for effecting contact between said circuitbreaker and a companion contact terminal, said casing parts and saidstab terminal member being provided with cooperating elements forreleasably retaining said stab terminal member in operative dispositionin said casing, said cooperating elements comprising laterally extendingportions of said stab terminal member and recessed portions in theconfronting surfaces of said complementary casing parts, said laterallyextending portions being removably engageable in said recessed portionswhereby said stab terminal member is supported in said casing parts inaxial disposition thereof.

20. In an automatic circuit breaker, an insulation casing havingportions defining a chamber in which the circuit breaker mechanism isdisposed and a chamber having an opening extending through the surfaceof said casing, one of said portions being common to said chambers andhaving an aperture therein, 4a stab terminal member mounted in saidlatter chamber and having a portion extending through said opening inthe casing surface for effecting contact with a companion contactterminal, @11d C01?- 12 ducting means extending through said aperture,one end of said conducting means being connected t0 said stab terminalmember, the other end thereof being connected to said circuit breakermechanism.

21. In an automatic circuit breaker, a casing provided with an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers being separated by a wall formed bycomplementary portions provided on confronting surfaces of said casing,one of said portions having raised end parts and the other of saidportions being removably engageable between said end parts, in abutmenttherewith, the confronting surfaces of said portions denning a guideway,a stationary contact disposed in said arcing chamber, a uni-planarmovable contact member mounted in the other chamber and having a portiondisposed in said guideway and extending into said arcing chamber, saidlatter portion being provided with a movable contact engageable with anddisengageable from said stationary contact, said wall encompassing saidlatter portion for confining arcing within said arcing chamber,actuating means for operatively effecting the engagement of saidcontacts, and a thermally responsive bi-metallic strip for effecting thedisengagement thereof, said strip being bodily carried by said movablecontact member, said actuating means being pivotally carried thereby andbeing in normal engagement with said strip to prevent relative pivotalmovement.

22. In an automatic circuit breaker, a casing having an open recessedportion and an arcing chamber adjacent thereto, said recessed portionand said arcing chamber being separated by an apertured portion of saidcasing forming a Wall of said chamber, a terminal member disposed insaid recessed portion and mounted on said wall, said member having acontact carrying part extending through said aperture and abutting thesurface of said wall opposite the surface on which said member ismounted, a movable contact engageable and disengageable with saidterminal contact, actuating means for operatively effecting theengagement thereof, a thermally-responsive bi-metallic strip foreffecting the disengagement thereof, and a uni-planar movable contactmember on which said movable Contact and said strip are bodily carried,said actuating means being pivotally carried thereby and being in normalengagement with said strip to prevent relative pivotal movement.

23. In an automatic circuit breaker, an insulation casing havingportions defining a chamber in which the circuit breaker mechanism isdisposed and a chamber having an opening extending through the surfaceof said casing, one of said portions being common to said chambers andhaving an aperture therein, a stab terminal member mounted in saidlatter chamber and having a portion extending through said opening inthe casing surface for effecting contact with a companion contactterminal, a stationary Contact, a movable contact engageable anddisengageable therewith, actuating means for operatively effecting theengagement thereof, a thermally-responsive bi-metallic strip foreffecting the disengagement thereof, a uniplanar movable contact memberon which said movable contact and said strip are bodily carried, saidactuating means being pivotally carried thereby and being in normalengagement with said strip t0 prevent relative pivotal move- 13 ment,and conducting means extending through said aperture, one end of saidconducting means being connected to said stab terminal member, the otherend thereof being connected to said strip.

24. In an automatic circuit breaker, a casing provided with an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers being separated by a wall formed bycomplementary portions provided on confronting surfaces of said casing,one of said portions having raised end parts and the other of saidportions being removably engageable between said end parts, in abutmenttherewith, the confronting surfaces of said portions dening a guideway,a stationary contact disposed in said arcing chamber, a uni-planarmovable contact member mounted in the other chamber and having a portiondisposed in said guideway and extending into said arcing chamber, saidlatter portion being provided with a movable contact engageable with anddisengageable from said stationary contact, said wall encompassing saidlatter portion for confining arcing within Said arcing chamber,actuating means for operatively effecting the engagement of saidcontacts, a thermally responsive bi-metallic strip for effecting thedisengagement thereof, said strip being bodily carried by said movablecontact member, said actuating means being pivotally carried thereby andbeing in normal engagement with said strip to prevent relative pivotalmovement, said casing having an open'recessed portion adjacent saidarcing chamber, said recessed portion and said arcing chamber beingseparated by an apertured portion of said casing forming another wall ofsaid arcing chamber, and a terminal member disposed in said recessedportion and mounted on said latter Wall, said terminal member having apart extending through said aperture and abutting the surface of saidlatter wall opposite the surface on which said member is mounted, saidstationary contact being carried by said extending part.

25. In an automatic circuit breaker, a casing provided with an arcingchamber and a chamber in Which'the circuit breaker mechanism isdisposed, said chamber being separated by a wall formed by complementaryportions provided on confronting surfaces of said casing, one of saidportions having raised end parts and the other of said portions beingremovably engageable between said end parts, in abutment therewith, theconfronting surfaces of said portions defining a guideway, a stationarycontact disposed in said arcing chamber, a uni-planar movable contactmember mounted in the other chamber and having a portion disposed in.said guideway and extending into said arcing chamber, said latterportion being provided with a movable contact engageable with anddisengageable from said stationary contact, said wall encompassing saidlatter portion for confining arcing within said arcing chamber,actuating means for operatively effecting the Vengagement of saidcontacts, a thermally responsive 1,ci-metallic strip for eifecting thedisengagement thereof, said strip being bodily carried by said movablecontact member, said actuating means being pivotally carried thereby andbeing in normal engagement with said strip to prevent relative pivotalmovement, said casing having an additional chamber provided with anopening extending through the surface of said casing, said casing havinga portion common to said additional chamber and the chamber containingthe circuit breaker mechanism, said common portion having an aperturetherein, a stab terminal member mounted in said additional chamber andhaving a portion extending through said opening in the casing surfacefor eifecting contact with a companion contact terminal, and conductingmeans extending through said aperture, one end of said conducting meansbeing connected to said stab terminal member, the other end thereofbeing connected to said strip.

26. In an automatic circuit breaker, an insulation casing havingportions defining a chamber in which the circuit breaker mechanism isdisposed and a chamber having an opening extending through thesurface ofsaid casing, one of said portions being common to said chambers andhaving an aperture therein, a stab terminal member mounted in saidlatter chamber and having a portion extending through said opening inthe casing surface for effecting contact with a companion contactterminal, a stationary contact, a movable contact engageable anddisengageable therewith, actuating means for operatively effecting theengagement thereof, a thermany-responsive bi-metallic strip foreffecting the disengagement thereof, a uni-planar movable contact memberon which said movable contact and said strip are bodily carried, saidactuating means being pivotallyk carried thereby and being in normalengagement with said strip to prevent relative pivotal movement,conducting means extending through said aperture, one end of saidconducting means being connected to said stab terminal member, the otherend thereof being connected to said strip, said casing having an openrecessed portion and an arcing chamber adjacent thereto, said recessedportion and said arcing chamber being separated by an apertured portionof said casing forming a wall of said arcing chamber, and a terminalmember disposed in said recessed portion and mounted on said latterwall, said latter terminal member having a part extending through saidlatter aperture and abutting the surface of said latter wall oppositethe surface in which said latter terminal member is mounted, saidstationary contact being carried by said extending part.

27. In an automatic circuit breaker, a casing provided with an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers being separated by a wall formed bycomplementary portions provided on confronting surfaces of said casing,one of said portions having raised end parts and the other of saidportions being removably engageable between said end parts, in abutmenttherewith, the confronting surfaces of said portions dening a guideway,a stationary contact disposed in said arcing chamber, a uni-planarmovable contact member mounted in the other chamber and having a portiondisposed in said guideway and extending into said arcing chamber, saidlatter portion being provided with a movable contact engageable with anddisengageable from said stationary contact, said wall encompassing saidlatter portion for confining arcing within said arcing chamber,actuating means for operatively effecting the engagement of saidcontacts, a thermally responsive lei-metallic strip for effecting thedisengagement thereof, said strip being bodily carried by said'movablecontact member, said actuating means being pivotally carried thereby andbeing in normal engagement with said strip to prevent relative pivotalmovement, said casing having an open recessed portion adjacent saidyarcing chamber', said recessed portion and said arcing chamber beingseparated by an apertured portion of said casing forming a wall of saidarcing chamber, a terminal member disposed in said recessed portion andmounted on said latter wall, said terminal member having a partextending through said aperture and abutting the surface of said latterwall opposite the surface on which said terminal member is mounted, saidstationary contact being carried by said extending part, said casinghaving an additional chamber provided with an opening extending throughthe surface of said casing, said casing having a portion common to saidadditional chamber and the chamber containing the circuit breakermechanism, said common portion having an aperture therein, a stabterminal member mounted in said additional chamber and having a portionextending through said opening in the casing surface for effectingcontact with a companion contact terminal, and conducting meansextending through said latter aperture, one end of said conducting meansbeing connected to said stab terminal member, the other end thereofbeing connected to said strip.

28. In an automatic circuit breaker, a casing provided With an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers being separated by a wall formed bycomplementary portions provided on confronting surfaces of said casing,one of said portions having raised end parts and the other of saidportions being removably engageable between said end parts, in abutmenttherewith, the confronting surfaces of said portions defining aguideway, a stationary contact disposed in said arcing chamber, amovable Contact member mounted in the other chamber and having a portiondisposed in said guidevvay and extending into said arcing chamber, saidlatter portion being provided with a movable contact engageable with anddisengageable from said stationary contact, said wall encompassing saidlatter portion for confining arcing Within said arcing chamber, saidcasing having an open recessed portion adjacent said arcing chamber,said recessed portion and said arcing chamber being separated by anapertured portion of said casing forming another wall of said arcingchamber, and a terminal member disposed in said recessed portion andmounted on said latter wall, said terminal member having a partextending through said aperture and abutting the surface of said latterwall opposite the surface on which said member is mounted, saidstationary contact being carried by said extending part.

29. In an automatic circuit breaker, a casing provided with an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers bein separated by a wall formed by complementaryportions provided on confronting surfaces of said casing, one of saidportions having raised end parts and the other of said portions beingremovably engageable between said end parts, in abutment therewith, theconfronting surfaces of said portions defining a guideway, a stationaryContact disposed in said arcing chamber, a movable contact membermounted in the other chamber and having a portion disposed in saidguideway and extending into Said arcing chamber, said latter portionbeing provided with a movable contact engageable with and disengageablefrom said stationary contact, said wall encompassing said latter portionfor conning arcing Within said arcing chamber, said casing having anadditional chamber provided with an opening extending through thesurface of said casing, said casing having a portion common to saidadditional chamber and the chamber containing the circuit breakermechanism, said common portion having an aperture therein, a stabterminal member mounted in said additional chamber and having a portionextending through said opening in the casing surface for effectingcontact with a companion Contact terminal, and conducting meansextending through said aperture, one end of said conducting means beingconnected to said stab terminal member, the other end thereof beingconnected to said circuit breaker mechanism.

30. In an automatic circuit breaker, an insulation casing havingportions deiining a chamber in which the circuit breaker mechanism isdisposed and a chamber having an opening extending through the surfaceof said casing, one of said portions being common to said chambers andhaving an aperture therein, a stab terminal member mounted in saidlatter chamber and having a portion extending through said opening inthe casing surface for eiiecting contact with a companion contactterminal, conducting means extending through said aperture, one end ofsaid conducting means being connected to said stab terminal member, theother end thereof being connected to said circuit breaker mechanism,said casing having an open recessed portion and an arcing chamberadjacent thereto, said recessed portion and said arcing chamber beingseparated by an apertured portion of said casing forming a wall of saidarcing chamber, and a terminal member disposed in said recessed portionand mounted on said wall, said latter terminal member having a contactcarrying part extending through said aperture and abutting the surfaceof said Wall opposite the surface on which said latter terminal memberis mounted, said circuit breaker mechanism being engageable with anddisengageable from said contact.

31. In an automatic circuit breaker, a casing provided With an arcingchamber and a chamber in which the circuit breaker mechanism isdisposed, said chambers being separated by a wall formed bycomplementary portions provided on confronting surfaces of said casing,one of said portions having raised end parts and the other of saidportions being removably engageable between said end parts, in abutmenttherewith, the confronting surfaces of said portions defining aguideway, a stationary contact disposed in said arcing chamber, amovable Contact member mounted in the other chamber and having a portiondisposed in said guideway and extending into said arcing chamber, saidlatter portion being provided with a movable contact engageable with anddisengageable from said stationary contact, said wall encompassing saidlatter portion for coniining arcing within said arcing chamber, saidcasing having an open recessed portion adjacent said arcing chamber,said recessed portion and said arcing chamber being separated by anapertured portion of said casing forming another wall of said arcingchamber, a terminal member disposed in said recessed portion and mountedon said latter wall, said terminal member having a part extendingthrough said aperture and abutting the surface of said latter wallopposite the surface on which said terminal member is mounted, saidstationary contact being carried by said extending part, said casinghaving an additional chamber provided with an opening' extending throughthe surface of said casing, said Casing having a portion common to saidadditional chamber and the chamber containing the circuit breakermechanism, said common portion having an aperture therein, a stabterminal member mounted in said additional chamber and having a portionextending through said opening in the casing surface for effectingcontact with a companion contact terminal, and conducting meansextending through said latter aperture, one end of said conducting meansbeing connected to said stab terminal member, the other end thereofbeing connected to said circuit breaker mechanism.

32. In an automatic circuit` breaker having a stationary contact, amovable contactv member mounted for pivotal movement and provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotallyA mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said f lever being formed in one piece andhaving laterally spaced parts disposed at opposite sides of said movablecontact member and an intermediate part connecting said spaced parts andhaving a surface portion providing a latch releasably engaged by saidcurrent responsive means to provide said releasable operative connectionof said lever to said movable contact member.

33. In an automatic circuit breaker having a stationary contact, amovable contact member mounted for pivotal movement and provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever having laterally spaced partsdisposed at opposite sides of said movable Contact member and anintermediate part connecting said spaced parts and having a surfaceportion providing a latch releasably engaged by said current responsivemeans to provide said releasable operative connection of said lever tosaid movable contact member.

34. In an automatic circuit breaker having a stationary contact, amovable contact member mounted for pivotal movement and provided with acontact engageable with and disengageablefrom said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever being formed of sheet metal andhaving a laterally extending surface part disposed transversely of saidymovable contact member, said surface part being adjacent a free end ofsaid lever and providingl a latching surface releasably engaged by saidcurrent responsive means to provide said releasable operative connectionof said lever to said movable contact member.

35. In an automatic circuit breaker having a stationary contact,A amovable contact member mounted for pivotal movement andA provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating. said movable contactv membercomprising ay lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever being formed of sheetk metal andhaving a laterally extending surfacer part disposed transversely of saidmovable contact member, said surface part being adjacent a free end ofsaid lever and providing a latching surface releasably engaged by saidcurrent responsive meansk to provide said releasable operativeconnection of said lever to said movable contact member, said current.responsive means comprising ak thermostatic strip having av free endabutting said latching surface in said releasable engagement of saidcurrent responsive means with said lever.

36; In an automatic, circuit breaker having a stationary contact, amovable contact member mounted for pivotal movement and provided With acontact engageable with and disengageable from said stationary contact;manually op.- erable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever being formed of sheet metal andhaving a laterally extending surface part disposed transversely of saidmovable` contact member, said surface part being adjacent a free end ofsaid lever and providing a latching surface releasably engaged by saidcurrent responsive meansy to provide said releasable operativeconnection of said lever to said movable contact member, said currentresponsive means comprising a thermostatic strip carried by said movablecontact member andV having a free end abutting said latchingy surfaceinsaid releasable engagement of said current responsive means With saidlever.

37. In an automatic circuit breaker having a stationary Contact, amovable contact member mounted for pivotal movement and provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever having laterally spaced partsdisposed at opposite sides of said movable contact member and anintermediate part connecting said spaced' parts and having aV surfaceportion providing a latch releasably engaged by said current responsivemeans to provide said releasable operative connection of said lever tosaid movable contact member, said current responsive means comprising athermostatic strip having a free end abutting said latching surface insaid releasable engagement of said current responsive means with said`lever.

38. In an automatic circ-uit breaker having a stationary contact, amovable Contact member mounted for pivotal movement and provided with acontact engageable with and disengageable,A from said stationarycontact; manually opera'ble means for actua-ting said movable contactmember comprising a lever pivotally mounted on said movable contactmember and current responsive means releasably connecting'said leveroperatively to said movable contact member, said lever being formed inone piece and having laterally spaced parts disposed at opposite sides`vof said movable contact member and an intermedi- A ate part connectingsaidspacedparts and, havingy a surface portion providing a latchreleasably7 engaged by said current responsive means to provide saidreleasable operative connection of said lever to said movable contactmember, said current responsive means comprising a thermostatic striphaving a free end abutting said latching surface in said releasableengagement of said current responsive means with said lever.

39. In an automatic circuit breaker having a stationary contact, amovable contact member mounted for pivotal movement and provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever being formed in one piece ofsheet metal and having laterally spaced parts disposed at opposite sidesof said movable contact member and an intermediate part connecting saidspaced parts and having a surface portion providing a latch releasablyengaged by said current responsive means to provide said releasableoperative connection of said lever to said movable contact member.

40. In an automatic circuit breaker having a stationary contact, amovable contact member mounted for pivotal movement and provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever being formed of sheet metal andhaving laterally spaced parts disposed at opposite sides of said movablecontact member and an intermediate part connecting said spaced parts andhaving a surface portion providing a latch releasably engaged by saidcurrent responsive means to provide said releasable operative connectionof said lever to said movable contact member, said current responsivemeans comprising a thermostatic strip carried by said movable contactmember and having a free end abutting said latching surface in saidreleasable engagement of said current responsive means with said lever.

4l. In an automatic circuit breaker having a stationary contact, amovable contact member mounted for pivotal movement and provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever being formed of sheet metal andhaving spaced sides provided with integral pivot elements engaging saidmovable contact member for said pivotal connection of said lever to saidmovable contact member, said lever having an integral part between saidsides disposed transversely of said movable contact member, said surfacepart being adjacent a free end of said lever and providing a latchingsurface releasably engaged by said current responsive means to providesaid releasable operative connection of said lever to said movablecontact member.

42. In an automatic circuit breaker having a stationary contacty amovable contact member mounted for pivotal movement and provided with acontact engageable with and disengageable from said stationary contact;manually operable means for actuating said movable contact membercomprising a lever pivotally mounted on said movable contact member andcurrent responsive means releasably connecting said lever operatively tosaid movable contact member, said lever being formed of sheet metal andhaving spaced sides provided with integral pivot elements engaging saidmovable contact member for said pivotal connection of said lever to saidmovable contact member, said lever having an integral part between saidsides disposed transversely of said movable contact member, said surfacepart being adjacent a free end of said lever and providing a latchingsurface releasably engaged by said current responsive means to providesaid releasable operative connection of said lever to said movablecontact member having a free end abutting said latching surface in saidreleasable engagement of said current responsive means With said lever.

43. In an automatic circuit breaker having a movable contact member, anactuating member carried by said movable contact member and a flexiblecontrol device for operatively connecting said actuating memberreleasably to said movable Contact member for operating the latterexcept when said control device is disconnected from said actuatingmember upon overload, a depending portion carried by said movablecontact member and extending through Said control device, and asubstantially rigid armature having a surface portion in abutment withsaid control device, said depending portion extending through saidarmature and being secured to an opposite surface portion thereof.

44. In an automatic circuit breaker having a movable contact member; anactuating member carried by said movable contact member, and a controldevice for operatively connecting said actuating member releasably tosaid movable contact member for operating the latter except when saidcontrol device is disconnected from said actuating member upon overload,said control device being xed in relation to said movable contactmember, and said actuating member being adjustable in relation to saidcontrol device to calibrate the circuit breaker for automatic openingthereof upon overload.

45. In an automatic circuit breaker having a movable contact member; anactuating member carried by said movable contact member, and a controldevice for operatively connecting said actuating member releasably tosaid movable contact member for operating the latter except when saidcontrol device is disconnected from said actuating member upon overload,said control device being fixed in relation to said movable contactmember, and said actuating member being adjustable in relation to saidcontrol device to calibrate the circuit breaker for automatic openingthereof upon overload, said movable contact member having a bendablepart and said actuating member being secured to Said bendable part.

46. In an automatic circuit breaker having a movable contact member; anactuating member carried by said movable contact member, and a controldevice for operatively connecting said actuating member releasably tosaid movable contact member for operating the latter except When saidcontrol device is disconnected from said actuating member upon overload,said control device being iixed in relation to said movable contactmember, and said actuating member being adjustable in relation to saidcontrol device to calibrate the circuit breaker for automatic openingthereof upon overload, said movable contact member having a bendablepart and said actuating member being secured to said bendable part, saidcontrol device being secured to said movable contact member at a pointthereof which is spaced from said bendable part.

47. In an automatic circuit breaker having a movable contact member; anactuating member carried by said movable contact member, and a controldevice for operatively `connecting said actuating member releasably tosaid movable contact member for operating the latter except When saidcontrol device is disconnected from said actuating member upon overload,said control device being xed in relation to said movable contactmember, and said actuating member being adjustable in relation to saidcontrol device to calibrate the circuit breaker for automatic openingthereof upon overload, said movable contact member having a bendablepart and said actuating member being secured to said bendable part, saidbendable part having an aperture defined in an edge thereof, and atapered member pressed into said aperture for bending said part.

48. In an automatic circuit breaker having a movable contact member; anactuating member carried by said movable contact member, and a controldevice for operatively connecting said actuating member releasably tosaid movable contact member for operating the latter except when saidcontrol device is disconnected from said ac- 9 tuating member uponoverload, said control device being fixed in relation to said movablecontact member, and said actuating member being adjustable in relationto said control device to calibrate the circuit breaker for automaticopening thereof upon overload, said control device being a bimetallicstrip having a free end engageable by said actuating member, and thelatter having an end portion which is adjusted in relation to said freeend of the bimetallic member by said adjustment of the actuating member.

49. In an automatic circuit breaker, an insulation casing formed ofcompanion complementary parts mutually secured in housing-definingrelation, and a stab terminal member contained in l said casing andhaving a portion extending therefrom for effecting contact between saidcircuit breaker and a companion contact terminal, said casing parts andsaid stab terminal member being provided with inter-engaging portionsfor releasl ably retaining said stab terminal member in operativedisposition in said casing, said interengaging portions comprisingintegral parts of said stab terminal member and integral portions ofsaid casing parts adapted to receive said integral stab parts,respectively.

50. In an automatic circuit breaker, an insulation casing formed ofcompanion complementary parts mutually secured in housing-definingrelation, and a prong terminal member carried by said casing, said prongmember having an end portion extending from said casing and a portiondisposed therein, said latter portion being provided with integralparts, and said casing parts having formations engageable with saidintegral parts for xing said prong in operative disposition therein,

51. In an automatic circuit breaker, an insulation casing formed ofcompanion complementary parts mutually secured in housing-definingrelation, and a prong terminal member carried by said casing, said prongmember having an end portion extending from said casing and a portiondisposed therein, said latter portion being provided with integralparts, and said casing parts having formations engageable with saidintegral parts for fixing said prong in operative disposition therein,said integral parts extending laterally from said prong member and saidcasing formations being in confronting disposition for receiving saidintegral parts, respectively.

52. In an automatic circuit breaker, an insulation casing provided witha longitudinally extending prong terminal member projecting therefrom,and cooperating means provided on said member and on said casing forsecurely retaining said member in longitudinal disposition thereoi` insaid casing.

53. In an automatic circuit breaker, an insulation casing provided witha longitudinally extending prong terminal member projecting therefrom,and cooperating means provided on said member and on said casing forsecurely retaining said member in longitudinal disposition thereof insaid casing, said means provided on said prong member being portionsthereof which extend transversely of said casing.

54. In an automatic circuit breaker, an insulation casing provided Witha longitudinally extending prong terminal member projecting therefrom,and cooperating means provided on said member and on said casing forsecurely retaining said member in longitudinal disposition thereof insaid casing, said means provided on said prong member being portionsthereof which extend transversely of said casing, and said meansprovided on said casing being confronting formations dened therein forreceiving said transversely extending portions.

THOMAS M. COLE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,662,970 Grosse Mar. 20, 1923 2,008,068 Gaynor July 16, 19352,157,787 Farrell May 9, 1939 2,209,319 Christensen July 30, 19402,209,352 Sachs et al. July 30, 1940 2,363,606 Maseng Nov. 28, 19442,419,072 Hall Apr, 15, 1947 2,450,268 Bazley Sept. 28, 1948 2,459,427Humpage Jan. 18, 1949

